This was leaking on #repop, unsure of other cases, smart pointers should
cover us though.

Direct leak of 3600 byte(s) in 18 object(s) allocated from:
    #0 0x7f2b3dbe0d30 in operator new(unsigned long) (/lib/x86_64-linux-gnu/libasan.so.5+0xead30)
    #1 0x5645dc7c9dff in ZoneDatabase::LoadSpawnGroups(char const*, unsigned short, SpawnGroupList*) ../zone/spawngroup.cpp:241
    #2 0x5645dc9db3f5 in Zone::Depop(bool) ../zone/zone.cpp:1746
    #3 0x5645dca1ba6b in Zone::Repop(unsigned int) ../zone/zone.cpp:1777
    #4 0x5645db4624b7 in command_repop(Client*, Seperator const*) ../zone/command.cpp:5683

Indirect leak of 6552 byte(s) in 273 object(s) allocated from:
    #0 0x7f26f2ff8d30 in operator new(unsigned long) (/lib/x86_64-linux-gnu/libasan.so.5+0xead30)
    #1 0x558d00490bc6 in __gnu_cxx::new_allocator<std::_List_node<SpawnEntry*> >::allocate(unsigned long, void const*) /usr/include/c++/8/ext/new_allocator.h:111
    #2 0x558d00490bc6 in std::allocator_traits<std::allocator<std::_List_node<SpawnEntry*> > >::allocate(std::allocator<std::_List_node<SpawnEntry*> >&, unsigned long) /usr/include/c++/8/bits/alloc_traits.h:436
    #3 0x558d00490bc6 in std::__cxx11::_List_base<SpawnEntry*, std::allocator<SpawnEntry*> >::_M_get_node() /usr/include/c++/8/bits/stl_list.h:450
    #4 0x558d00490bc6 in std::_List_node<SpawnEntry*>* std::__cxx11::list<SpawnEntry*, std::allocator<SpawnEntry*> >::_M_create_node<SpawnEntry* const&>(SpawnEntry* const&) /usr/include/c++/8/bits/stl_list.h:642
    #5 0x558d00490bc6 in void std::__cxx11::list<SpawnEntry*, std::allocator<SpawnEntry*> >::_M_insert<SpawnEntry* const&>(std::_List_iterator<SpawnEntry*>, SpawnEntry* const&) /usr/include/c++/8/bits/stl_list.h:1903
    #6 0x558d00490bc6 in std::__cxx11::list<SpawnEntry*, std::allocator<SpawnEntry*> >::push_back(SpawnEntry* const&) /usr/include/c++/8/bits/stl_list.h:1220
    #7 0x558d00490bc6 in SpawnGroup::AddSpawnEntry(SpawnEntry*) ../zone/spawngroup.cpp:122
    #8 0x558d00490bc6 in ZoneDatabase::LoadSpawnGroups(char const*, unsigned short, SpawnGroupList*) ../zone/spawngroup.cpp:291
    #9 0x558d006a1465 in Zone::Depop(bool) ../zone/zone.cpp:1746
    #10 0x558d006e1adb in Zone::Repop(unsigned int) ../zone/zone.cpp:1777